repo for user contribs? (was: Re: Official policy on LLM-assisted contributions)

> [...] the bottleneck is rarely the pace
> of offered contributions (bug reports,
> patches, bug fixes) -- it's the time that
> maintainers can spend assessing them.

So what are your thoughts on an extra
repo where contributions can be shared,
reviewed, stabilized & forward-ported until
-- if ever -- they make their way into mainline?

I'm thinking of allowing one or two orders of
magnitude more committers than in the main
repo, basically giving access to all serious users.
Any stable contribs ready for merge could be
automatically found at any point in time, simply
via branch & tag naming conventions.

Especially the burden of monthly forward-porting
from one release to the next could likely be eased
significantly by fellow users, and even to a large
degree assisted by coding agents, without adding
any risks to the main repo. (That way I managed
to forward-port "allocation tracks" from 2.5.5
to master today, with the AI tracing conflicts 
back to upstream commits and coming up with
correct solutions AFAICT.)

Any objections, concerns, suggestions?
PMs welcome as well.

Cheers,
Andreas